167Bug Vector Table And Workspace - Motorola MVME167 Series Installation Manual

Using the 167Bug Debugger
5

167Bug Vector Table and Workspace

5-12
167Bug uses certain of the MVME167 onboard resources and may
also use offboard system memory to contain temporary variables,
exception vectors, etc. If you disturb resources upon which 167Bug
depends, then the debugger may function unreliably or not at all.
If your application enables translation through the Memory
Management Units (MMUs), and if your application utilizes
resources of the debugger (e.g., system calls), your application must
create the necessary translation tables for the debugger to have
access to its various resources. The debugger honors the enabling of
the MMUs; it does not disable translation.
As described in Memory Requirements on page 4-5, 167Bug needs
64KB of read/write memory to operate.
167Bug
reserves ...
1024-byte area A user program vector table area
1024-byte area An exception vector table for the debugger itself to use
Space for static variables and initializes these static variables to
predeÞned default values.
Space for the system stack then initializes the system stack pointer to
the top of this area.
With the exception of the first 1024-byte vector table area, you must
be extremely careful not to use the above-mentioned memory areas
for other purposes.
Refer to Memory Requirements on page 4-5 to determine how to
dictate the location of the reserved memory areas.
For ...